linux/drivers/acpi/arm64/amba.c
Youwan Wang bfe3f0df3e ACPI / amba: Drop unnecessary check for registered amba_dummy_clk
amba_register_dummy_clk() is called only once from acpi_amba_init()
and acpi_amba_init() itself is called once during the initialisation.
amba_dummy_clk can't be initialised before this in any other code
path and hence the check for already registered amba_dummy_clk is
not necessary. Drop the same.

Signed-off-by: Youwan Wang <youwan@nfschina.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Hanjun Guo <guohanjun@huawei.com>
Link: https://lore.kernel.org/r/20240624023101.369633-1-youwan@nfschina.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-06-24 18:36:07 +01:00

118 lines
2.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* ACPI support for platform bus type.
*
* Copyright (C) 2015, Linaro Ltd
* Author: Graeme Gregory <graeme.gregory@linaro.org>
*/
#include <linux/acpi.h>
#include <linux/amba/bus.h>
#include <linux/clkdev.h>
#include <linux/clk-provider.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include "init.h"
static const struct acpi_device_id amba_id_list[] = {
{"ARMH0061", 0}, /* PL061 GPIO Device */
{"ARMH0330", 0}, /* ARM DMA Controller DMA-330 */
{"", 0},
};
static void amba_register_dummy_clk(void)
{
struct clk *amba_dummy_clk;
amba_dummy_clk = clk_register_fixed_rate(NULL, "apb_pclk", NULL, 0, 0);
clk_register_clkdev(amba_dummy_clk, "apb_pclk", NULL);
}
static int amba_handler_attach(struct acpi_device *adev,
const struct acpi_device_id *id)
{
struct acpi_device *parent = acpi_dev_parent(adev);
struct amba_device *dev;
struct resource_entry *rentry;
struct list_head resource_list;
bool address_found = false;
int irq_no = 0;
int ret;
/* If the ACPI node already has a physical device attached, skip it. */
if (adev->physical_node_count)
return 0;
dev = amba_device_alloc(dev_name(&adev->dev), 0, 0);
if (!dev) {
dev_err(&adev->dev, "%s(): amba_device_alloc() failed\n",
__func__);
return -ENOMEM;
}
INIT_LIST_HEAD(&resource_list);
ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
if (ret < 0)
goto err_free;
list_for_each_entry(rentry, &resource_list, node) {
switch (resource_type(rentry->res)) {
case IORESOURCE_MEM:
if (!address_found) {
dev->res = *rentry->res;
dev->res.name = dev_name(&dev->dev);
address_found = true;
}
break;
case IORESOURCE_IRQ:
if (irq_no < AMBA_NR_IRQS)
dev->irq[irq_no++] = rentry->res->start;
break;
default:
dev_warn(&adev->dev, "Invalid resource\n");
break;
}
}
acpi_dev_free_resource_list(&resource_list);
/*
* If the ACPI node has a parent and that parent has a physical device
* attached to it, that physical device should be the parent of
* the amba device we are about to create.
*/
if (parent)
dev->dev.parent = acpi_get_first_physical_node(parent);
device_set_node(&dev->dev, acpi_fwnode_handle(adev));
ret = amba_device_add(dev, &iomem_resource);
if (ret) {
dev_err(&adev->dev, "%s(): amba_device_add() failed (%d)\n",
__func__, ret);
goto err_free;
}
return 1;
err_free:
amba_device_put(dev);
return ret;
}
static struct acpi_scan_handler amba_handler = {
.ids = amba_id_list,
.attach = amba_handler_attach,
};
void __init acpi_amba_init(void)
{
amba_register_dummy_clk();
acpi_scan_add_handler(&amba_handler);
}